Police said Mason Campbell, 12, fired a 20-gauge shotgun three times in the Berrendo Middle School gym Tuesday, injuring two students.

Authorities charged Campbell with counts of aggravated battery with a deadly weapon. He's currently in a psychiatric hospital in Albuquerque.

According to our media partners at the Albuquerque Journal, Campbell posted on Instagram the Sunday before the shooting: "Tomorrow will be the first Monday that will be fun for me lol never thought I'd say that."

Berrendo Middle School was closed Monday because of a water line break, the Journal reports.

The two children injured in the shooting are Kendal Sanders, 13, and Nathaniel Tavarez, 12. Both are in a Lubbock hospital next to each other.

Tavarez is in critical condition with injuries to his eyes, head and chest. Sanders is in satisfactory condition with injuries to her arm.